猪源抗腹泻芽孢益生菌的分离与Z-27菌株的鉴定

Isolation of Probiotics Strains with Anti-diarrhea Effects from Pig and Identification of Strain Z-27

为了获得对腹泻病原菌有拮抗作用的益生菌株,采集健康仔猪的粪便为试样,以0.5%的猪胆酸盐为筛选压力,以大肠杆菌(Eacterium coli)K88菌株作为病原指示菌,筛选对大肠杆菌具有拮抗作用的产芽孢菌株。通过初筛,共得到对大肠杆菌具有拮抗作用的菌株18株,进一步复筛出1株拮抗活性较高的菌株Z-27。根据形态和生理生化特征,初步鉴定Z-27菌株为Bacillus velezensis,结合对Z-27菌株的16S rDNA序列分析结果,最终鉴定Z-27菌株为Bacillus velezensis。

To obtain probiotics strains with anti-diarrhea effects, with the screening stress of 0.5% bile salts of pig, 18 pro- biotics pig origin Bacillus spp. strains with antagonistic activities against Eacterium coli were isolated from the feces of pigs. And from the 18 strains obtained via preliminary screening, a strain named Z-27 with relatively higher antagonistic activity was obtained via secondary screening. Then the strain Z-27 was characterized by a series of physiological and biochemical experiments and morphological and culture features observation. Based on the results, the strain was initially identified as Bacillus velezensis. Then 16S rDNA sequence analysis of the strain was carried on. According to the results, strain Z-27 was finally identified as Bacillus velezeusis.